Cost-effectiveness of using continuous positive airway pressure in the treatment of severe obstructive sleep apnoea/hypopnoea syndrome in the UK.

OBJECTIVE: A study was undertaken to estimate the cost-effectiveness of using continuous positive airway pressure (CPAP) in the management of patients with severe obstructive sleep apnoea/hypopnoea syndrome (OSAHS) compared with no treatment from the perspective of the UK's National Health Service (NHS). METHODS: A Markov model was constructed to assess the cost-effectiveness of CPAP compared with no treatment. The model depicted the management of a 55-year-old patient with severe OSAHS as defined by an apnoea-hypopnoea index (AHI) >30 and daytime sleepiness (Epworth Sleepiness Scale score >or=12). The model spans a period of 14 years. RESULTS: According to the model, 57% of untreated patients are expected to be alive at the end of 14 years compared with 72% of patients treated with CPAP. Untreated patients are expected to cost the NHS pound10 645 (95% CI pound7988 to pound14,098) per patient over 14 years compared with pound9672 (95% CI pound8057 to pound12,860) per CPAP-treated patient. Treatment with CPAP for a period of 1 year was found not to be a cost-effective option since the cost per quality-adjusted life year (QALY) gained is expected to be > pound20,000, but after 2 years of treatment the cost per QALY gained is expected to be pound10,000 or less and, after 13 years of treatment, CPAP becomes a dominant treatment (ie, more effective than no treatment for less cost). CONCLUSION: Within the limitations of the model, CPAP was found to be clinically more effective than no treatment and, from the perspective of the UK's NHS, a cost-effective strategy after a minimum of 2 years of treatment.